Dog Days and Nights
by gummyshoes
Summary: Ever since experimenting with gene splicing during his Uni days, Sherlock has been hiding the fact that he has a dog's tail, ears, and urges from everyone but John. When he creates a serum to make John develop similar features, the two quickly discover that it's either a blessing...or a curse. [Animal Transformation, graphic descriptions, pain, embarrassment, puppy!sherlock/!john]
1. Chapter 1

I've developed a serum that would...modify you. To make you more like me. You seem to enjoy my 'extra features'. I thought maybe you'd like them on yourself, too. SH

You mean... I mean... I like them /on you/, but I don't know... JW

I don't know if I can live that way. Would I get... like, dog thoughts or something? JW

If you did, they would probably be minor. I have a few from time to time. For example, sometimes when you're sleeping I'll lick your cheek rather than kiss it. SH

[delayed] Oh... and... like dogs piss on stuff to mark their territory. Have you ever...? JW

Would I... have urges like that? JW

Such a personal question, John. I don't know. You might. It's no different than any medication; you know the intended result, but the side effects vary patient to patient. SH

You still didn't answer the question. JW

I did when I was younger. Haven't for years. SH

How long have you been that way? With the 'extra features'? JW

Since I was nineteen. I wanted to experiment with gene splicing. There was only so much I could do with corpses. Tried it on myself, and the rest you know. SH

So... the medication for me. What /is/ the intended result, exactly? JW

A tail and ears. I think you'd look fantastic with both. SH

Blond, I assume? JW

Of course. I used some hairs from your brush in the serum. SH

I don't want you to feel pressured, John. SH

So... would I take pills? JW

For chemical, you know. Restoration or something. JW

Shouldn't have to. The new DNA should bind with what you have now. SH

Okay. JW

Um... so you hide your ears with a deerstalker, yeah? JW

How do you fit your tail? JW

I tie it to my leg. I'll be honest, it's not comfortable. SH

Does it move... like, on its own? JW

Like a dog's, yes. SH

It has a mind of its own then? JW

Well, more or less. Its actions are directly related to my mind. SH

But I don't will it to move, correct. SH

So if you're happy...? JW

It wags. Yes. Fortunately, I can normally keep it under control. The only time I can't is when I'm at the flat, with you. SH

[delayed] That's sweet actually. JW

If you're sad or something, does it ever tuck between your arsecheeks? JW

[Delayed] Maybe. SH

God. That can't be comfortable. JW

It's not. Part of the reason I try so hard to avoid negative emotions. SH

Right. JW

[delayed] Do you ever feel like just walking around the flat nude? I mean, it would be a lot less confining for your tail and all. JW

I have considered it. However, there is the issue of Mrs. Hudson and my brother or his minions walking in whenever they feel like. SH

Nobody else knows about me, John. I need to keep it that way. SH

I know. And you're trying to make me like you. JW

Selfish, isn't it? SH

Why can't anyone know? JW

Because I would be treated as a lab rat. Questioned. Studied. Observed. SH

Right. JW

Your brother doesn't even know? JW

I don't think so. He probably knows I'm hiding something, but it's been almost twenty years and he's never made mention. SH

[delayed] I'll do it. JW

How the hell did you get your tail though? Did it sprout out or did you, like, sew it on? JW

Was it painful? JW

No, it grew out of me. I won't lie, it was exceedingly painful. SH

How long did the pain last? JW

Until it was finished growing. Took about an hour. A little less. SH

Fortunately, we have something known as 'morphine' to help in these sorts of situations. SH

Okay... and your ears? Did that hurt? JW

What happened to your human ears? JW

Not near as badly. It wasn't comfortable, but they stretched outwards. Grew hair. SH

The hair growth is unpleasant. Very itchy. SH

I assume it has something to do with the pores opening up. SH

You're not making this very convincing. JW

I just want to be open and honest with you on what to expect. SH

Okay, so pain above my arsecrack, /exceeding/ pain, itchiness, hair-how much hair grows on me? JW

It'll be long, like mine. SH

Should only be on your tail and ears. SH

My tail will be long? JW

I meant your hair. Your tail will probably be too. SH

My hair on my head? How long? JW

Will, like, my beard growth be more rapid too? JW

I meant the hair on your tail and ears, John. It might. Mine wasn't affected. SH

Do you ever cut it? JW

The hair on your tail and ears. JW

I haven't, no. I might do so, though. I tested this serum on myself to ensure it would be safe for you, and my tail and ears both lengthened and grew thicker fur. SH

How long is your tail? I've only seen it once or twice. JW

It was about a foot. Now closer to a foot and a half. SH

That's going to be even worse now. JW

Yes, I know. It's not easy. SH

Do you like it? JW

It's part of me, John. SH

I know, but not everyone likes every part of them. I don't like my nose. JW

[Delayed] Before I met you, I had considered amputation. SH

Seemed easier than hiding it. SH

Why did you stop thinking about it when you met me? JW

Because you accepted my abrasive personality, my selfishness, my 'abilities'. I assumed a tail wouldn't even make you blink an eye. SH

No. It's quite... cool. And you did it to yourself. It was... ballsy as fuck. JW

Mm. Probably not the best decision I've ever made, but it is nice to be unique in other ways. Also it's somewhat, dare I say, lonely. SH

[delayed] That's why you want me to do it? JW

Partly, yes. I also think you'd look even more appealing with the features. SH

[delayed] Do you ever get majorly horny because of it? In some sort of mating season or some shit? JW

Ha. Dogs are always majorly horny. But no, I don't. Hasn't happened yet. SH

I'm no more of a 'normal' dog than I am a normal human, John. SH

So you're just a normal guy with dog ears and a tail. JW

Who has repressed other urges. Such as licking your face on a constant basis. Such as asking you to scratch me behind my ears. Whimpering when I'm unhappy. Et cetera. SH

What's the et cetera? Come on, I want to know everything if it's going to happen to me. JW

That's really about it. You've heard me growl before. It sounds very human, but it's a canine impulse. SH

Right. JW

The way I want to sleep right beside you. Again, canine. SH

Do you ever curl up in a ball? Circle around before lying down? JW

I have done both, yes. SH

More so before we started sharing a bed. SH

Why don't you now? JW

I wouldn't mind. JW

Now that I know you wouldn't mind, I might start doing it again. SH

It would be cute. JW

/Cute/. How insulting. SH

I don't know if you know this, but you are majorly adorable. JW

What a terrible thing to say to me. Anything I can do to make me /not/ be majorly adorable? SH

Shit on the carpet. JW

Oh, Christ, John. /Jesus/. Vulgar. SH

My dog used to do that, and it was most certainly not adorable. JW

If you ever piss me off, I will keep that in mind. SH

You better not. JW

I am normally in complete control of my bladder and bowels. SH

Normally? JW

Very rarely the instincts take over. Had to leave a crime scene once because I let it out in my bloody trousers. Fortunately, I had my coat on. SH

I had been on the scene for hours. No loos. SH

But that's not even canine, just a human left with no more will. JW

It was canine in that I went where I was. If it'd been human, I would have insisted upon leaving. My thoughts were strange that day. It was before I met you, when I was using drugs. A bit not good. SH

If it'd been human, I would have at least pissed outside of my trousers. Instead the thought didn't even occur to me. SH

Ah. Like the canine part of you didn't even realize you had trousers? JW

Essentially. All I knew was that I had to piss and shit; I didn't think about taking my pants and trousers off first, or making a mad break to go behind a tree. SH

Gross, you had to do both? JW

I was humiliated. And I can't believe that I told you that just now. SH

I peed myself when I was six once. JW

You were a child. Not a grown man. SH

Okay, yeah, but... yeah, that's embarrassing. JW

Very. I don't think you'll encounter such urges. SH

If you do, I apologise in advance. SH

Any /good/ things about being part canine? JW

You'll sleep well. Relax easier. Perhaps become more easily amused. Didn't work for me, but you're more genial to begin with. SH

The ears and tail are both very sensitive. SH

Sensitive? JW

Like, to scratching and stuff or to pain? JW

In a good way. SH

If I don't do it, I'd still be glad to scratch behind your ears. Or above your bum. JW

Both, I suppose. Sitting on my tail hurts more than stubbing my toe. SH

I noticed you do that sometimes, and your tail kind of curls up. JW

I would very much like it if you scratched me in those places. Yes, it does, it doesn't take well to pain. Then again, what does? SH

Right... so, to recap: a lot of pain to grow, no horny urges, maybe accidentally pissing yourself, nice scratches, good sleep, and we'll be the only ones known to man like this. JW

Piss or both. Hopefully neither. The rest seems accurate. SH

Give me some time to think on it. JW

Of course. The serum keeps for two days. SH

What do you mean? JW

It won't work after two days? JW

Very short shelf-life. SH

Right. JW

Okay. So I have two days to think on it. Should be enough. JW

And you could always make it again right? JW

Of course. SH

Okay. JW

Another question: were you the reason that there are mysterious teeth marks on the corner of the coffee table? JW

I might be. I got antsy. Bored. That was the night you were with your date for nearly eight hours. SH

So you chew on stuff. JW

Very rarely. But yes. SH

Will I? JW

Is it like Twilight where the baby vampires are, like, unable to control their urges? JW

Don't judge. My last girlfriend wanted to watch it. JW

I don't know anything about Twilight or vampires. SH

It's hard to say. As I said, your serum will be diluted. You won't suddenly act completely canine. SH

It will be gradual. JW

That's not what I meant. I meant you might have urges that you can learn to control. SH

Will the urges be immediate? Will I control them once I first have them or does it take time to learn how to control it? JW

Are there any urges you can't control? JW

It takes a bit of time. I haven't found anything, but then, I'm me. I have an extraordinary capacity for controlling myself, dog or not. SH

Right. You arsehole, though, you better not judge me if I piss myself or something. JW

I won't. Of course not. SH

Do you drool? JW

Like a dog? Not during your sleep or something. JW

No. Sometimes I'll pant, but it's another thing that I hide very well. SH

You've had practice suppressing it too. Was it hard at first? JW

Well. It certainly wasn't easy. SH

But, dogs can be trained. You'll teach yourself, just as I did. SH

I'd like to see you pant. A bit. JW

Do you ever hold back in front of me? JW

Why do you want to see that? And yes, all the time. SH

I want to see you be entirely you. JW

What do you hold back? Why? JW

The panting. The whimpering. The urge to nuzzle against you, lick you. SH

Christ, did I really just say 'nuzzle'? SH

It's cute. JW

It's embarrassing. SH

Yeah, well, I'm about to go through it too, so don't worry. I don't have nearly the amount of self-control you do, so... ought to be fantastic. JW

You'll learn, John. I'll help you. SH

I'll do it. JW

And if I try to back out, tell me no. Swat my nose with a rolled up newspaper or something. JW

I am glad that you're doing this with me. For me. SH

And for me too. JW

It will be interesting. JW

When will you be home? SH

Soon. Getting work off for the next few weeks. JW

Probably a good idea. Bring dinner. Pizza, tomatoes on my half. SH

Wouldn't be a bad idea to get yourself some morphine, either. SH

What, just steal some from the clinic? JW

Problem? SH

Bit unethical. JW

John, it will hurt. You'll want something. SH

All right. JW

Fine. JW

Sherlock set his phone down on the coffee table. The serum was in the fridge, all of its components mingling together. Sherlock was still becoming accustomed to his longer, furrier ears and tail. They would be harder to hide now, but John was worth it on all levels. Besides, who else could he have tested it on? Mrs. Hudson? Jesus. Sherlock pulled the blanket over his body and yawned; he hadn't slept well for the past week because he'd been so focused on finishing the serum before his samples went bad. Now, it was finished, and John was willing to take it. It actually made Sherlock /happy/. His eyes fell shut, and he nodded in and out of sleep while he waited.


	2. Chapter 2

**Yay for chapters! I'm not sure if I should break them up more or leave them long as they are, let me know if it's bothersome. Feedback is always appreciated, and thanks for reading. :)**

John sighed, packets of morphine stuffed into his coat pocket as he tried to breeze past everyone without looking suspicious. Is this what it would feel like having a tail and ears? Always feeling you had something to hide, like someone could see something was wrong with you? At least it wasn't illegal to have a tail. Not officially anyway. Waving to the receptionist, John smiled and then hurried out of the building, hailing a cab as he stopped by to get pizza to bring home to his furry and hungry companion. John loved Sherlock more than anything, and he was crazily interested in knowing about his life, his transformation. He was terrified of doing this, but he wanted it. It would be a change. One they would go through together. John had grabbed two pizzas, in case the side effects included increased appetite, and he entered the flat, whistling because he knew Sherlock was receptive to high-pitched noises. "Sherlock," he called, laying the pizzas down. "You ready?"

Sherlock stretched awake on the couch, rolling his back as each vertebrae in his spine cracked into place. He hadn't realised how tense he'd been, but the nap had done him good. He stood up and brought his arms over his head, yawning as he joined John in the kitchen. "I've been ready," he answered, grinning a little as he leaned in to kiss John. After what John had told him, though, he changed his mind at the last second and licked the doctor's cheek instead. That was what he wanted, wasn't it? Sherlock did love licking John, and it wasn't just because of the salty taste of his skin. He just truly liked to be affectionate with him. Not that he would ever admit to it. He wouldn't. He sat down at the table, carefully feeding his longer tail through one of the open slits in the back of his chair, and nodded, gesturing towards the fridge. "Serum's in there. You can mix it with some water and drink it. Should start in about ten, fifteen minutes. Gives us time to eat."

John grinned whenever Sherlock did, his lips lopsided into a smirk, and he chuckled, raising his brows in surprise as he felt a wet, slimy heat glazed over his cheek. It gave a little stir downstairs, and he furrowed his brows, wondering why. It was an odd feeling, tongue to skin, but it wasn't unpleasant, not at enough. John chuckled; he still liked kissing, but he was allowed like both, right? And maybe after the serum, he wouldn't like kissing as much. Maybe not at all. Maybe he would like licking. Too many thoughts. John shook his head and nodded to Sherlock. "Am I allowed to eat before this?" he asked, opening up the fridge and peering into the disgusting-looking liquid. It was the color of baby vomit and the consistency of it too. "It smells disgusting," John commented, wafting it to his nose and gagging a bit. God, tonight would not be pleasant; he was still uncertain of what exactly he was going to be experiencing: nausea, relentless urination, sexual urges, but the only thing he was certain of was the pain. He wasn't looking forward to that. He checked the packets of morphine in his jacket before sighing and closing his eyes, collecting his thoughts. It wouldn't be that bad. It couldn't be.

John's smile, small as it was, encouraged Sherlock. He felt...not guilty, but concerned, that he had done the wrong thing by asking John to join him in this. Sherlock knew from experience how much it hurt and how terrifying it was, but, at least he'd be with him through the whole thing. And, John had morphine. Everything would be fine. He truly believed that. "Yes," Sherlock answered, opening one of the pizzas and getting a slice of tomato for himself out and then pushing the box towards John's chair. "Come here and eat. Everything is going to be fine, John. The changes will be minimal; that's how I designed the serum. Any mental changes that happen, if any, we'll be able to deal with. I have every confidence in you." He could tell that John was apprehensive, so Sherlock leaned over and took his hand, lightly squeezing it in encouragement before letting it go again. "Once everything's over with, we'll go about our lives. Helping each other hide when we're in public, being ourselves here at the flat." It would be a relief to not have to hide his urges, few as they were, in his own home anymore.

John nodded and ventured towards the table, sitting down. He noted that Sherlock's tail was free, and he glanced towards it, assessing its length. Yeah, it had definitely grown. It was massive now, furrier. As were his ears. They seemed too floppy, like he was a pup who wasn't big enough to grow into his ears, and it only added to his cuteness. John grinned, knowing Sherlock would hate to hear his throat. John grabbed a slice of pizza, humming before hissing. "Hot!" he exclaimed. "Ah." He set the pizza down over the box again and took a moment before picking it up, blowing on it to try and cool it off before taking another bite. He found comfort in the way Sherlock spoke, without apprehension and without concern. John smiled, swallowing the pizza before eating in silence, thinking too much to be distracted by talking. He drew himself out of his thoughts whenever Sherlock mentioned being in public. He was very worried about his tail-and wearing a hat wasn't always allowed. Maybe he could get away with it if he mentioned he had a mole or something. That would be embarrassing but no worse than a simple, "Hey, yeah, sorry, my dog-boyfriend helped me turn into a permanent part-werewolf, sorry about that." John shook away the thoughts as he nibbled on the crust of his pizza, having devoured a whole slice in under a minute. He grabbed a second and smiled, giggling at the size of Sherlock's ears, imagining him shake his whole body like a dog after a bath with his huge ears slapping his cheeks.

John was being very quiet. It was unnerving, really. Sherlock had expected questions, comments. /Something/. When John giggled, though, Sherlock's brow furrowed. "What's so funny?" What was he laughing at? The idea? The way that Sherlock had slaved over a serum for weeks? Something that had happened at work? Could be anything. Sherlock wasn't the best at reading emotions, nor was he the best at showing them. That was another thing that he'd repressed over the years. Even so, though, hearing John's laugh made Sherlock huff, hoping to disguise it as a scoff when really it was a short laugh of his own. If that weren't enough of an indication that he enjoyed John laughing and actually appearing at ease, despite what was about to happen, then the way that his tail started swaying behind him most certainly would be. It wasn't a pleasant feeling, the base of his tail being caught by the chair whenever it swept from side to side, but he was used to it after having the appendage for almost twenty years. He had been a little surprised when John hadn't encouraged him to go through with an amputation. Then again, John didn't mind the tail at all, or his ears, or the way he would-rarely-bark. He never had. Sherlock was a little worried that seeing John experiencing canine instincts, if he even did, would make his own come out more. There was a reason Sherlock avoided dogs, and it wasn't /just/ Redbeard. John being like him would make that unavoidable.

John raised his brows whenever Sherlock asked him the question, sounding almost offended by John's laughter. John scoffed out a laugh, shaking his head as he chewed on his lower lip, his eyes crinkled by his smile. "Nothing." He was worried about the serum and the change, but that was the thing about Sherlock that he loved: no matter what was happening, he made it feel like everything was under control. They'd been shot at together, they'd been screamed at together, they'd been in dangerous and nerve-wracking situations times and times before, but John rarely felt his nerves because he always felt like Sherlock had it under control. Like when you're a kid and you have a nightmare and sleeping in your parents' bed makes you feel better. It's just an overall sense of safety that Sherlock proved for him, and John adored and appreciated it. Laughing whenever he saw the look on Sherlock's face, John shook his head and approached Sherlock, threading his fingers through the longer hairs on his tail, using his other hand to scratch behind Sherlock's ears. "I was just thinking of how adorable you looked with your too-long tail and your floppy, too-big ears," John mumbled, a peaceful and teasing grin on his face as he bent down, pressing an affectionate kiss to Sherlock's forehead. Keeping his lips there, John paused, thinking for a moment, before flicking out his tongue in a brief kiss to Sherlock's skin.

Sherlock watched John as he stood up, curious as to where he was going and /why/. When John touched him, though, he stopped caring. He made a soft noise in his throat, something between a grunt and a hum, when John's fingers went into the fur of his tail, and when John's hand went to work, fingers digging into the spot just behind his ear, he inhaled sharply. Christ, that felt good. /So/ good. He tried to rub at his own ears, but it never gave him any sort of pleasure, just like a person couldn't tickle themselves, he supposed. It would be more convenient if it were like masturbating-not the preferred method, but still give the desired relief if a companion couldn't be found. When John started to speak, Sherlock opened his eyes (when had they even shut?) and looked at the doctor's face. He could vaguely tell that his own leg was shaking, but he tried as hard as he could to not draw attention to it. "I don't like that word. 'Adorable'." Even so, his tail started to beat back and forth faster, a combination of the compliment and John's hands. When he was kissed, Sherlock hummed, content, but when he was /licked/, he gasped. That had felt perfect. Sherlock returned the favour by tilting his head up and licking across John's lips, then his chin. "You're embarrassing me right now. I hope you know that."

Honestly, John had never expected Sherlock to be so responsive to something as simple as waggling his fingers back and forth against his ears. It was amazing to see Sherlock react that way, making those noises, to something as simple as that. John chuckled and removed his hand from behind Sherlock in order to rub a hand up and down his side. "Good boy." Was that demeaning for Sherlock? Was it rude? Would he like it? He didn't know, but he liked the way it sounded, even though John was about to be his equal-physical, complete equal. On the intellect stance, Sherlock was above and beyond. Physically, he was gorgeous, with or without the extra appendages. John licked his lips whenever Sherlock looked up with him, and at the feeling of his boyfriend's tongue swiped across his chin and lips, he smiled and laughed, slightly shocked, slightly surprised, and slightly pleased by that. He wiped off the spit and kneeled down, loving the way that Sherlock's leg thumped against the ground in enjoyment, and John stopped scratching behind his ear, touching his bobbing knee. "Why are you embarrassed?" he laughed. "I'm the one who should be embarrassed. God knows what the canine in me will do." John laughed and shook his head, scratching his finger at the curve of Sherlock's jawline, wondering what other spots liked to be scratched. "Just don't laugh at me."

John was right about that. All things considered, he /should/ be embarrassed. Growing a tail and dog ears in front of somebody, well...that wasn't the most dignified thing one could do. He was fully confident, though, that John would be fine. Any canine urges could be dealt with. As Sherlock had said, dogs can be taught, trained, to act the way that you want them to. And John was so obedient to begin with...it shouldn't be hard. Sherlock tilted his head, trying to follow John's hand even as it left his ears. He suddenly felt naked without John's hands on him in this sensitive places, and he very much didn't like it. It caused his tail to slow in its wagging. John Watson could be a complete tease without even realising that he was doing it. Or was that the definition of 'tease'? He was relieved when John's hand ended up back on him, at his jaw. "I won't laugh at you," he promised. "I suppose the reason I'm embarrassed is because acting like a dog is rather, well, undignified. And you /know/ how much I value my dignity." Even so, Sherlock tilted his head, trying to get his ear back under John's hand again. It did work, and Sherlock resorted to turning his head fully and lapping his tongue at John's palm. The licking was loud, wet, and Sherlock felt...both mortified with himself, and completely at ease. Strange that the two could be so conflicting, yet occur simultaneously.

John grinned, biting on his lower lip, as his nerves caught up with him. He was going to grow a tail. /Grow/ a fucking /tail/. Normal people don't just grow a tail, but normal people also don't live with people who have. Normal people don't agree to voluntarily grow a tail. John was plain, he was completely and entirely normal; he wasn't the type of man you would look at and expect to have a freaky flatmate who enjoyed being treated like a canine. But you wouldn't look at him and expect him to /want/ to be part-canine either. The world is full of surprises. Sherlock didn't react negatively to the 'good boy', so John expected it was okay, and if it wasn't, Sherlock could correct him. "Thanks," John mumbled, laughing as is boyfriend's tongue lapped against his skin. "That tickles," he mumbled, and he withdrew his other free hand and carded his fingers through Sherlock's hair before scratching behind his ear. The licking was loud, and it reminded him of whenever his childhood dog would pin him to the floor and cover him with drool and kisses, the way John would laugh and struggle beneath the dog. The sound was like a slapping noise, or maybe a clapping one, of tongue to lips. Sherlock's kisses were a bit rough from the texture of his tongue but soft with the wetness, and John shook his head. "You are the most dignified, respectable, serious man I have ever met," John said. "I think it's okay to let yourself loose a little while." John smiled and stood, ruffling Sherlock's hair before turning towards the serum. His arms hung limp by his side, and he glanced towards Sherlock's slowing tail before sighing. "Right then," he said, picking up the glass container the serum was held within. "Let's go."

Dignified. Respectable. Serious. They were all glorious compliments, and exactly what he needed to hear while he was 'lowering' himself to lick John's hand. His tail was wagging again, swaying side to side jauntily at John's flattery and also the sensations that John was making him feel. He even smiled a little himself when John touched his ear again. It was making him not only happy but also excited. Down /there/. That probably wasn't the best thing to admit to, but it was an undeniable fact that Sherlock was getting aroused by the attention as much as it was making him feel relaxed and, possibly more than anything, /loved/. He had never had a friend before John, never had anyone that he could tell about his differences. But then john had entered into his life and Sherlock had told him about them fairly quickly. John was /John/. He was kind and caring, nonjudgmental, open-minded, patient, gentle. Sherlock could have gone on, and maybe he would have if John was as much of a fan of flattery as he was. He stood up when instructed and poured John a glass of water from the sink. "Might be best if you swallow all of that-" he pointed towards the syringe-"at once and then rinse it down with the water." He put his hand on John's back and guided him towards the couch, taking care to move his tail out of the way of both of them before lowering himself onto it. "Let me know everything that you're feeling, the minute you start to feel it." Sherlock leaned over and kissed the corner of John's mouth, a proper kiss this time, as if to show John that he most certainly remembered how to give them. "Everything's going to be fine."

John was dizzy. Now that the moment was coming, he realized how totally unprepared he was. He had thought about it, and he had thought about it in depth, ways to get around and prepare and schedule his life around it. He was ready. He was using up his vacation time for a training camp to make his canine urges less, and he was ready. Except, there was a bottle of baby vomit waiting to be drank by him and it would inevitably lead to a path of pain and suffering and embarrassment all at once. He would have to experience all he was experiencing in front of Sherlock. John glanced down in the bottle again and swirled the thick substance around, trying not to gag from the smell. John glanced to Sherlock whenever he spoke, and he nodded to show he had a vague understanding of what Sherlock was trying to convey to him, and he cleared his throat. "Yeah," he said, and he was guided to the couch, where he sat down without thought-he would have to be careful whenever he grew a tail. It was sensitive, Sherlock said. John paused and set the bottle down. "I-I should take off my trousers. For when my tail grows." John paused, licking his lips. "First... the... the, um, stuff." Was he losing his ability to speak English too? John sighed and rubbed his hand into his eyes before reaching forward, scratching behind Sherlock's ear. He smiled and chuckled whenever Sherlock kissed him. "Thank you," he whispered before clearing his throat. "Bottoms up," he mumbled before downing the drink. Immediately, he gagged and coughed, though he forced himself into swallowing it. With a loud groan, John reached forwards desperately. "Water, water," he said, grappling for the bottle as he chugged it down.

"It's not /that/ bad, surely," Sherlock said with a slight roll of his eyes, although he himself had nearly gagged from the smell, too. DNA and tissue samples, genes, a bit of cerebrospinal fluid-all in all, not an entirely complicated mix, but it was enough to make the smell and taste pungent. Sherlock wondered, briefly, if he could have found anyone else willing to agree as quickly as John had. not necessarily agree to it for Sherlock's sake, but for their own. He didn't know anyone off the top of his head that would. Molly? No, too timid. Mycroft? Bloody hell, no. Sherlock wouldn't ever even bother asking. Lestrade? No. Although a dog's nose /would/ be useful in helping him with cases. It certainly served Sherlock well. Those were really he only three people that Sherlock had to even consider. Perhaps if the serum was mass-produced, more people would be interested. People who were unhappy with their normal, boring lives and wanted something to make them unique because they couldn't find anything themselves. 'Everybody's unique, everybody's special'. His mother had used to tell him that when he was young. Some people were unique in that they were more boring than other boring people. When the serum was down John's throat, Sherlock reached for the television remote and dropped it into John's lap. "Pick something. You may as well relax," he instructed. "No need to take your trousers off now. You'll feel when it starts to grow; you can take them off before it gets too painful." He knew that John was embarrassed, so he was actually trying to be /kind/ (so unlike him) and make John feel at ease.

No going back now. The awful substance was now settling in his stomach, being corroded by his stomach acid, and there was a faint stomach ache, like the substance was actually fighting back against the natural duties of his bodily functions. He felt a punch from the inside of his gut and groaned, clutching it. "Jesus Christ," he mumbled, rubbing at his abdomen. He was about to ask what the hell was in it, but he feared what would be the answer. Going from the smell, it couldn't be too pleasant. John glanced down at the remote in his lap that had been dropped down by his boyfriend, and John nodded. His stomach was settled, though there was still a vague taste in his throat and he wiped off his tongue with his thumb, his arm extending to Sherlock. "C'mere," he ordered, wanting to snuggle for as long as he could before doing what he would assume would be like a man's transformation into a werewolf on a full moon: a lot of screaming, grunting, and then finally howling as he clutched and grunted, trying to ease the pain as he sprouted an entire new limb. He felt the faint singe of regret that was eased by the cute sight of Sherlock with his ears and his waggly tail. John would have one of those. In an hour or so, he would have his own waggly tail and his own wiggly ears, and he tried to imagine what it would feel like: the constant sway of an extra limb rocking him, reacting to his emotions, his feelings. He wondered how much it would move. If he could control it. John chuckled. "Come here," he said again, curling his fingers as he brushed his knuckles up against Sherlock's cheek.

Sherlock watch watching John with complete and utter fascination. He really had just drank it, all of it, He hadn't imagined things. He hadn't hallucinated. John was going to have ears and a tail like him, and Sherlock knew without even having to see them that he was going to look fantastic. John compliment his own appendages and Sherlock always shrugged it off, not understanding /what/ John saw in them...but now that it was soon to be his turn to see somebody /else/ with the features, he understood perfectly. When John lifted his arm and prodded him, again, to come closer, Sherlock nodded wordlessly and scooted over on the couch, feeling John's arm slip around his shoulders. He liked cuddling more than he would ever admit. One could even go so far as to call him a 'lap dog'. Obviously, though, he wasn't like that with anyone but John. That was why he had an easier time repressing his urges when he was out of the flat. He didn't care about being himself, he didn't care that he was hiding a part of himself. With John, he had. His ear was being bent and smashed against John's shoulder; he had to reach up and fumble with it a little before he could get it in a position that wasn't uncomfortable. Going from having ears that resembled a retriever's to having ones that looked more akin to a bloodhound's (although furrier) was a change. Oh, well. He would just have to wear that bloody deerstalker more. John would enjoy that, he would have more opportunities to tease him about it. Sherlock wrapped his arm around John, over his stomach, and sighed heavily, tail waving lazily behind him.

John flicked through the telly channels, skimming his eyes through the words, even though he was more focused on the weight of Sherlock's head against his shoulder. Cuddling was always difficult since John preferred to be the big spoon but would always have Sherlock's tail thumping up against his crotch all night, which was just as distracting as it was adorable. Now, his tail and ears were larger and more noticeable but they were also in the way far more often. Feeling Sherlock adjust, John tilted his shoulder away so he would have space to move his ear to make it comfortable. Once his cheek was lain back over John's shoulder, he smiled, brushing the man's bangs away from his forehead so he could see his face better. He loved cuddling with Sherlock, and he couldn't wait to hear the noises since he wasn't holding back anymore. John could tell form the licks and the whines and the scratches that they were going to be more open with each other, especially about this, and he couldn't wait to hear and see and experience with Sherlock what it was like. It was crazy and amazing and extraordinary, and John smiled, licking at Sherlock's temple. He tasted of salt, and nothing much more than that, but it was a sweet flavor too, one that he didn't particularly hate and almost kind of enjoyed. John really didn't feel any different; if anything, he felt better, knowing something again would draw them closer together, would bind them together, which wasn't a bad thing. John was attracted to Sherlock in every way and he was sure he'd love to be with him his whole life. Doctor Who played reruns on the telly as John's hand trailed onto Sherlock's leg and then lifted to his ear, scratching behind it casually, as John watched Ten and Donna argue like children.

Sherlock's mind was swimming with questions, just as he was sure John's probably was. Would John ever bark? How long would his tail be? How long would his ears be? Sherlock was fairly confident that the fur would be long and, he found himself thinking, he /hoped/ it was. And, he was also confident that John wouldn't /lose/ his ability to speak. Barking would be an urge that he may or may not get, but he'd talk. There was just no way to take the serum from a hybrid, dilute it, and then have the end result being /more/ canine than the original samples, which were his own. He wondered if they would have more sex after this. Sherlock wasn't an extremely sexual creature, dog or not. He'd been a virgin, /completely/ inexperienced, before John, and even now they only had sex once a week or so. John had never said that he'd wanted more, but maybe he'd been resisting. Maybe he had known that Sherlock was uncomfortable with having his innermost urges exposed like that. Or, maybe once a week was just enough to satiate John. Would that be different after his transformation? /Would/ John ever urinate-or more-while he was fully dressed? Sherlock's dignity and cleverness hadn't stopped /him/ from doing it, after all. Christ, he still remembered that day, feeling the warmth in the back and front of his trousers, having to leave the scene /immediately/ and come home and wash both his body and tail. Nothing in his life could ever come close to humiliating him as much as that had. When John started scratching his ear, Sherlock tilted his head, guiding John's fingers to right where he wanted them. It made him relax, and his eyes fell shut while his hand started to slowly rub John's stomach. The clock was ticking (literally, he could hear it), and he found himself counting away the minutes rather than watching the show on the telly.

John was trying to suppress the questions flying through his mind with every passing second because he didn't know the answers. He wouldn't know the answers. Not for an hour-a long, painful hour of transformation; but it couldn't hurt worse than a bullet wound, could it?-and John was impatient. His leg bounced up and down, and his subconsciously followed Sherlock's silent instructions of where to put his fingers, and he continued scratching, stopping only momentarily as he looked down to see Sherlock's hand rubbing over his stomach. He'd never done that before. Maybe it was what he, as a hybrid, liked. Is that what he was? A hybrid? God, that sounded so impersonal, like he was more of an experiment than a living human being. Maybe he would try it out sometime on Sherlock-rubbing his stomach. Dogs liked that, right? And that seemed to be how Sherlock preferred his affection: more canine than human. John was okay with that, and maybe since he would know what it feels like, he would like it too. If Sherlock was rubbing his stomach in order to show him what affection was like, maybe Sherlock would also like if John were to do that for him. God, there were so many things to try and so many things to try out, so many unanswered questions that would only be answered with time. There were so many 'what ifs' that terrified him to the put where he just ignored them, and as he asked, "How much time has passed?", he felt an ache in his lower back. John frowned and rubbed at his back, carefully pushing Sherlock off of him. Oh, shit. "Shit," John breathed, glancing hesitantly to Sherlock, unsure of what to do. A pulsing pain throbbed his lower back, like a heartbeat in rhythm, though it felt more like there was a tennis ball being thrown into the lowest part of his spine, constant and bouncing back, back, back, back. John furrowed his brows and grunted, rubbing at his skin. "Sherlock," he said, unsure of what to do now. Take his trousers off? Sherlock had seen him naked before, and it wasn't a big deal but somehow at the thought of it, John's cheeks reddened with embarrassment and he felt more vulnerable and insecure than he ever had.


	3. Chapter 3

**This story is a bit graphic so far as describing the transformation goes. Lots of mentioned pain, so if that's not your thing, might be best to avoid this one. Feedback is always appreciated, thanks to those of you who've left reviews :) Enjoy!**

Everything had been going perfectly, but then he was suddenly being guided upwards and John was cursing. Not that that was unusual; John had quite a foul mouth on him. Sherlock had always attributed it to his years as a soldier. Given John's initial question, though, Sherlock could only assume that he had been asking right in the midst of a change beginning to happen. "What is it?" Sherlock asked as he sat up, tail pausing in its wags and just hanging there, still, behind him. Then he saw John's hand go to his low back, rubbing at it, and Sherlock hummed in understanding. He knew. He'd been there before. It wasn't pleasant, not at all, but at least John would have his morphine. Sherlock still remembered-clearly-transformation. He'd been downright terrified, although not quite...surprised. After all, he had willingly mixed canine and human DNA and then /consumed/ it. Frankly, though, he thought that he would be met with a bad stomachache, possibly a migraine for a few days. When the tail started growing out of his back, he'd been shocked by /that/. He was also confused by things, even back then, like how the hair on his head was curly, but the fur on his tail and ears was straight. Not that he minded; it made it much easier to brush.

Sherlock's own cheeks turned a bit red at that, joining John's. Yes, he brushed his tail. The fur would get matted sometimes and it pulled on the nerves; it was uncomfortable. Brushing it regularly helped that. "Where's the morphine?" Sherlock leaned forward and retrieved the bottle of water off the coffee table for John to swallow his pills with. It was probably best that he take it now, before the pain increased. He put his hand on John's shoulder and gently guided him to lean forward, while his other hand pulled up his jumper. He looked at where John had been rubbing. There was nothing yet, but it was starting to turn a bit pinkish, and when Sherlock touched the area it felt hot. "At least we know the serum's working," he said in an attempt to add some light to the situation and comfort John. He put the bottle of water into his partner's hand and slid his arm fully around his shoulders, then nosed at his cheek. "It's all right, John. The morphine will help immensely. Take it."

John furrowed his brow, sucking at his lip, as he wondered what this sort of pain equated to. Currently, it felt like an aching feeling that just pulsated and was growing worse by the second. "H-how long does this last again?" John asked, even though he knew the answer. His mind seemed to think by asking again it may reduce the number of minutes he would have tolerate the pain. John tilted his head back, puffing out a hot breath and grunting as he tried to suppress the pain. "Yeah," he mumbled, his eyes clenched shut. God! What had once felt like a tennis ball now felt like a heavy bag of sand that pounded up against his vertebrae, as if trying to crack his spine and open up a hole in his back. John mumbled something indecipherable which was supposed to answer the morphine question, and he patted around his chest before reaching into his pocket to grab the packet. "Here we go," he muttered, ripping it apart using his teeth. He popped two pills into the palm of his hand and then patted them into his mouth, gulping down two sips of water as he sighed. John grunted lightly whenever he felt Sherlock nosing into his cheek, and he grinned lightly, though that immediately faded whenever a thud against his back enough to make his muscles quake began, and he yelled out.

"Jesus fucking Christ," John hissed, rubbing at his back. He wondered if this was what giving birth was like, except rather than his back from his crotch. Jesus, that wouldn't be pleasant. John leaned forward, rubbing his back. His skin was searing hot, and he leaned over so much his head was nearly between his knees as he tried to rub away the pain, clenching his jaw tightly to keep the shouts inside his mouth. With nowhere to go, the screams he held back were forced down his esophagus into his stomach, and he nearly felt like he was going to vomit. With a sigh, he called out, just to relieve some of the pressure in his back and chest. "Sherlock," he whimpered, turning his head to look at the man. He extended his hand, while his right one was clenching the cushion of the couch, his fingernail driving into the fabric. God, it hurt. "Is... how long... does...?" John shifted his shoulders in obvious discomfort. As of right now, it was aching and then discomfort and then pressure, an exploding amount of pressure that dappled his vision.

Even though Sherlock had known what to expect, imagining it wasn't near as horrible as witnessing it. He wasn't okay with this. Not at all. Seeing John wincing and having to force out every exhale, choke down each inhalation-no, it wasn't good, not at all. Sherlock was instantly having doubts, instantly, thinking that he'd been selfish and cruel (neither were uncommon for him) to ask this of John, knowing deep down the whole time that John would say yes out of love and loyalty. Sherlock immediately took John's hand when it was offered to him, holding it tightly and licking it in a futile attempt to comfort his partner. "The morphine will help." Christ, he kept saying that. It was the only comforting thing he could think to say. What else was he to tell John? 'Sorry, but you're stuck with it'. 'Sorry, it'll be half an hour to an hour'. 'Sorry, there's nothing I can do for you'. 'Sorry, it's too late to stop it now'. 'Sorry, I didn't create any sort of antidote'. No, no, definitely not. Sherlock considered getting off the couch so that he could kneel down in front of John, pull the doctor into his arms, but then he wouldn't be able to monitor the growth of the tail to see how it was doing, if everything was going according to how he'd planned it out in his mind. Speaking of, he could have done better with the planning. Put John in a medically-induced coma, got better pain medication, /something/. When his eyes met John's, and Sherlock could see the pain and fear in them, he whined. It was a perfectly canine noise, high-pitched, scared. He hadn't meant to do it. He hadn't known that it was coming. His instincts were betraying him, betraying how much he hated to see John going through this, even though he had /expected/ it. A quick glance at John's back showed that a small, barely noticeable (to anyone but Sherlock Holmes) bump had formed on the base of his spine, no doubt what would soon develop into the tail. It wanted to grow, it wanted to wag, it wanted to be a part of John. Unfortunately, there was a very unpleasant time to come between now and when that was a complete process. "Shh," Sherlock said, attempting to soothe John as he wrapped his other arm around him to join the one at his shoulders. He pulled John closer to him and kissed his temple, then licked it. "It's started to grow. That's good. It means everything's working just as it should."

John hissed out a breath through his nostrils, clenching his eyes shut, as he doubled over, trying to reduce the amount of pressure on his spine, trying to do anything to reduce the pain. God, it hurt so badly; his ears were ringing uncontrollably, a loud, piercing sound that made Sherlock's voice bubbly, as if he were underwater, and John squeezed Sherlock's hand so tightly he thought he would break his fingers. Somehow, he managed not to care, which was incredibly distressful. He never liked to cause Sherlock pain, but-"Goddamn it!" John shouted, grunting as he tilted his head back, letting out sharp and painful breaths. The inhale and exhale scraped against his burning lungs, and he panted, reminding himself of a dog and reminding himself that was the reason he was in this mess. He didn't like causing Sherlock pain, but he found himself focusing on nothing more than the feeling of bone spontaneously growing in accompany to his spine. "Oh, God, Sherlock," John breathed heavily, his chest rising and falling quickly, rapidly, his heart pounding against his ribcage. It was utter agony; fire burned at his back, and he could feel every portion of the tail growing and spurting-trying to break through the barrier of muscle and the thin lining of skin that protected him.

John sighed and breathed out heavily, his grip loosening slightly on Sherlock's hand. His tail seemed to be giving him a break, and his face relaxed slightly. His hand that was nearly white from griping the couch cushion was brought up to his hair, and he gripped it tightly as another round of pain started. How could Sherlock do this? At least John currently had a source of encouragement and two pills of morphine streaming through his bloodstream-how badly would it feel without it? The licks on his hand and temple cooled with the thin layer of sweat forming from suppressing the pain and grunting. "You...," John whispered, shaking Sherlock's hand against the couch, as he grunted, suppressing another yell through his gritted teeth. It felt like his voice would punch through his jaw in order to let him scream, and he opened up his mouth with another shout. How long had it been? "How long... how much longer?" John demanded, glancing up to Sherlock, pain in his eyes as he blinked away tears. "Is it almost... out?" Was that the word? God, this was like giving birth except /for a tail/. John shivered a sigh and shook his head, another short few seconds of painless bliss. "Sherlock..."

The way John kept saying his name was making the sour feeling of guilt grow in Sherlock's stomach. John kept looking to him, as if he would be able to offer answers, be able to tell him exactly how much longer he had to suffer, how much longer it would last. The fact was that Sherlock didn't /know/. He had absolutely no idea, and could only judge based on how long it had taken his own tail to grow and how long John's currently was which, he hated to admit, wasn't all /that/ long. About two inches, two and a half at most. At least it was growing steadily. The skin on John's...tail...was red, just like the inflamed area that it was sprouting from. It was going to take a bit of getting used to, thinking of John actually having a tail just like he did. Sherlock could already picture running his fingers through the fur, gently stroking it as John slept, helping John to tie it to his leg before they went out. All it would take was a bit more time and pain. Sherlock didn't think that lightly, but that /was/ all that stood between them and it being complete. John might have some slight canine urges, but he would still be /John/. His human DNA wasn't going anywhere; he would just have to adjust to having some canine tendencies here and there.

"It's growing," was all Sherlock said, because he couldn't bring himself to tell John, 'you've got a way's to go yet'. At least he wasn't lying. John seemed to be getting brief spurts of relief from the pain; Sherlock was entirely sure what was the cause of that, because he hadn't been that lucky. The morphine? It had to be the morphine. As Sherlock stared at John's tail, leaning down to try and inspect it, he could see very, /very/ fine hairs beginning to come from it. "Oh, look," he said, attempting to be cheerful, encouraging, even though John couldn't /actually/ look, "the fur's coming in. Can you feel it, does it itch?" It had itched like hell when Sherlock's fur had grown. "You should have long hair, since it's modeled off my own tail." The hairs were barely visible, but Sherlock's human eyes-actually better than a dog's when looking at things up close like this-were locked on them, looking for them.

John furrowed his brows, humming as his feet bounced, and after a moment, the aching disappeared. Expecting another blow, John kept his eyes shut, his brows furrowed, his lips pressed together into a thin line, and he fluttered his lashes. What? No, that couldn't possibly be it. It had only been about ten, fifteen minutes, and it wasn't nearly as bad as he expected. Hesitantly, John looked to Sherlock, confusion plastered on his face. Sherlock had said it was growing; that was all he had said, but that didn't mean anything. Right now, it felt like a small, little spike prodding out of his lower back, nothing much, and John was just about to ask if it was over when an explosion of hot, searing pain burst through him. He shouted out immediately, and he grabbed at the cushion of the couch and then Sherlock's forearm, his fingernails daggering into the man's flesh. It wasn't aching anymore. There was no pressure; instead, it was searing, hot agony burning through him, the stretching throb of his bones elongating from his back, forming into a whole new limb. His vision was dappled again by stars, and he was in dizzying pain, so much so he thought he would faint. He clutched Sherlock's arms, actual tears down his face now, as he felt the limb growing-millimeter by millimeter, and it was so achingly slow that John cried out. Pain rocketed through him, launching throughout his body, a whole new tier of pain, and he grunted, leaning over.

"Trousers," John said, desperate to give it as much room as possible, not to confine it-the mere twitching of the newly sprouted tail was sending shoots and bullets of pain through him, like bullets were ricocheting off his vertebrae. John's trembling fingers struggled to undo the button of his jeans, and he unzipped it quickly, shouting out in agony before wracking out a whine. He kicked off the trousers, leaving him only in pants, and he screamed out with another burning whip of pain.

Sherlock should have done that proactively, had John take his pants and trousers off. Why hadn't he? Christ. He'd been too preoccupied with seeing John, with being happy about what he was agreeing to do, that he hadn't been thinking straight, it seemed. Perhaps giving into his canine impulses was /not/ the smartest idea, now or ever. Poor, poor John. Dear, sweet John, going through this, all for Sherlock. Sherlock had never seen John cry before. He'd been dumped by countless (not actually countless, the number was six) girlfriends, seen horrific things in the war and often had nightmares about it, dealt with an alcoholic sister and parents that had always been absent, but Sherlock had never seen him in physical pain. He wondered briefly if John had cried when he'd been shot, before telling himself that that wasn't anywhere near being an appropriate thing to think about right now. Not that he'd ever cared about being appropriate. Sherlock wet his lips; he was uncomfortable, so uncomfortable to be sitting here right now, knowing that he was the cause of all this, /directly/ the cause of it. "It's all right," Sherlock said again, gently, as he reached down to push John's pants under his arse, just making sure that they were out of the way.

"Good thing it doesn't have to rip through your clothes, isn't it?" Sherlock's had nearly had to do that, and it was /agony/ to feel the growing limb trying to sprout its way out of his trousers. Sherlock considered reaching out to touch it, to see if that would make it feel better or worse. He enjoyed having his own tail touched because it did feel /fantastic/, but John's was still in the growing stages, very sensitive and probably in a bad sort of way. Sherlock tightened his arms around his partner and licked his ear, caressing the lobe with his tongue. Anything. He would do /anything/ right now to help John through this.

John breathed out a relaxed sigh whenever his trousers were down; God, he couldn't believe that he'd actually had the mind to be /embarrassed/. John felt as though he was nearly shitting himself and if he did, he wouldn't even have the /mind/ to be embarrassed for he was in such massive pain there was little that could be done to distract him. John breathed out, his fingers clenching into his palms, as with Sherlock moving, he didn't have anything to hold onto. Whenever his fingers extended, there were little crescent-shaped cut, bleeding out and stinging with the sweat on his palms, though that felt more like an orgasm compared to the pain he was feeling now. John's breath faltered as he clenched his eyes shut and he nodded before whimpering, shoving his face into Sherlock's chest, biting down into his shirt, even nipping a bit at his skin. He couldn't care, he wasn't caring at all. "Fuck," he whined, stomping his foot as he growled into Sherlock's chest. Every millimeter the tail grew was another minute of pain, and John was sure he would never survive this. How could he survive this? John breathed, focused on breathing. In, out, in, out, in out, inout, inoutinoutinout-"Fuck!" John sobbed, pushing his skull deeper into Sherlock's chest, his fingers curling around his shoulder blade, putting enough pressure on his bone to crush it. "Fuck me, fuck," he cried, shaking his head. "Can't, I can't..."

But he /had/ to. He felt as if he were dying; the pain alone was enough to make his vision black and his brain numb, and it was never-ending. "Fuck." By now, the tail was only four inches long, nowhere near finished growing, and it had been about twenty minutes. John, of course, wasn't placing any blames. One: he wasn't in the right mind to, and two: that's not who he is. John panted out and groaned, lifting his chin as Sherlock licked him, and he cooed in reply, pressing his sweaty forehead to Sherlock's neck. "Keep... talking... tell me... about anything. Give me something to focus on," John ordered, his words rushed as if he wasn't going to have enough breath to say them all. John puffed out his cheeks and groan before yelling out, feeling as though his body was just being pulled apart, bone from bone.

Sherlock didn't say a word when John bit him, or when his hand /clenched/ his body. It hurt, it hurt /terribly/, but he knew that it was absolutely nothing compared to what John was going through. The slew of obscenities, the wracking sobs, tears streaming down his face. And all Sherlock could do was sit and watch, try to comfort him. He rubbed his hand across John's shoulders, deciding that it was probably best to avoid touching anywhere near the sprouting tail right now. His other hand threaded into John's hair and he massaged his scalp with his fingertips, slowly and gently. "I promise, I'll make it up to you," he said, the words ending in another canine whimper when John released another loud cry. Thank /God/ Mrs. Hudson was away for the evening. If she came up here and saw...this...whatever the hell this even was; how would he go and describe that? She would probably insist on taking John to the hospital, to which Sherlock would say no, because then people would see him, they would know. At this point she would notice his ears, his tail; she'd probably scream and panic, wondering what was happening to 'her boys'. He and John would both be taken in by the government, sent away to some lab to be tested. Mycroft would come in and look at him, condescendingly, disgusted. Hadn't this seemed like such a good idea before? Now it was just bordering on being horrifying.

"It'll feel /so/ much better soon," Sherlock promised. That wasn't entirely helpful to say, he knew, because it didn't solve the problem of there being another half-hour or so to go like this. And, John's ears still needed to change. Sherlock glanced at them from time to time, but there didn't appear to be much of anything happening to them. Yet. "Can you take more morphine?" Sherlock hadn't wanted to ask; he didn't want to make John think about dosages and calculations when he was in this sort of state, but he wouldn't risk giving him another pill, and he wasn't about to let John out of his arms when that seemed to be the only thing that /did/ help the doctor.

John's ears twitched, and he turned his head to the side whenever he heard Sherlock's whimper. He sounded so puppyish so sweet and innocent that John's lips twitched against his shoulder, spasming into something like a half-smile. God, Sherlock was so goddamned cute; John better be twice that whenever this damned tail finished growing. He couldn't take more of this; this couldn't keep going. John breathed into Sherlock's shirt, the heat of his breath intermingling with the man's skin, and John grunted and snarled, his teeth sinking into the fabric and causing a few tears. John licked his teeth as he turned on his side, his legs stretched out. John panted, his body limp for a few moments as he was seemingly given a break. Oh! Oh, there it was, there it fucking was. "Itching," John explained as he curled up onto all fours, clutching Sherlock by the bicep as he rammed his skull into the man's chest. "/God/," John shouted, the little hairs on his tail burning, yearning to be itched as they each individually grew, along with the rocketing pain of the elongating tail.

"God, fuck!" John whined, practically blubbering as his lips wavered into a frown and he hiccupped a sob. "Sh-Sherlock," he whimpered, his toes curling. He loved the feeling of fingers running through his hair, and he made whines, whimpering, desperate, little whines that still sounded partially human, though incredibly babyish-like those an infant would make. John hated himself in this moment. he was weak in front of Sherlock, and he was sniveling and crying, but he cut himself some slack. This was by far the worst pain he'd ever felt. It would be better. It would be better, Sherlock promised that, and John forced himself into believing him as he sniffled, snot drizzling from his nose. It was another ten minutes of grunts and shouts and tormented whines before his ears began to stretch, folding over themselves and growing patches of golden hair over them, a slow process. Occasionally, John lifted a fist from Sherlock's bicep and swatted at his ear, using his knuckles the scratch the itch, though that only resulted in pain and burning. John grunted in frustration, one hand on the other's shoulder and the other on Sherlock's thigh before he squeezed, gritting his teeth. "Sherlock," John growled, "give me something. I need it. Hand it to me." John glared up at the man, anger in his eyes, not because Sherlock wasn't adequate or that he was the cause of this but because John himself was so weak he needed pills and so weak that he didn't care. John whined and whimpered, shoving his face into Sherlock's shirt as if he were trying to suffocate himself.

"Of course," Sherlock said, quickly, grabbing at John's trousers with his feet and scooting them across the floor to where he could reach them. It was a challenge to bend down and fish them out of John's pocket, but he got the packet and slipped one tablet between John's lips. Just one for now, with the ever-looming threat of a damned overdose in Sherlock's mind. At least John's ears were growing, and Sherlock already found himself thinking-and he felt guilty for doing so, now of all times-that they looked fantastic on his lover. Floppy, wiggly, /cute/. Sherlock, again, thought that maybe he should touch them. Maybe touching them would feel good, like it felt good when his own were touched, or maybe he could at least scratch them and help to relieve some of the itching. When he saw John try it though, grunting in discomfort whenever his hand came into contact with the thin flaps of fuzzy skin, he decided against it. Clearly it wasn't the time for that, /clearly/ they were still too sensitive to touch. John's cries were gradually become more canine, although they still could have passed as human to anyone who wasn't paying much attention. Which, usually, was everyone. Sherlock pulled the blanket off the back of the couch and wrapped it around his hand, using it to wipe the sweat and mucous and tears off of John's face. He was the cause of this. All of it. If he'd never made his own serum to begin with twenty years ago, John wouldn't be in the midst of a traumatising experience. If he hadn't asked John to take the serum, John would be /fine/. They'd be eating takeout and watching James Bond movies, rather than John being a crying, sniveling mess from being /tortured/.

Ironically, Sherlock was the one who would have resulting injuries. Bruises on his arms, shoulders, and hand from where John had clenched them, bite marks on his chest. John wouldn't have injuries; he would just have a long, fluffy tail and ears. It was almost a humorous contrast. "Do you remember," Sherlock began, reaching behind John's head to keep rubbing at his hair while being sure to avoid touching his ears, "our first case? You barely knew me, yet you shot a man for me. You knew that other people didn't like me; you knew that I rubbed people the wrong way, that I had a history of drug abuse, that I alienated people. And yet, you risked having yourself incarcerated or filled with mental anguish for the rest of your life, all for me." Sherlock forced a smile onto his face, although it was still small given everything that was happening. "That was when I knew that I would tell you about me."

John whined, scratching noises scraping against his throat, a high-pitched noise that escaped his lips with a natural flow, like he wasn't even trying, and he swallowed the pill that left a bitter and dry taste in his mouth. He couldn't complain; that was supposed to help him. He wasn't in his right mind to think about overdose when something so much worse was already ailing him, but he knew that more would make him better. John's hand trailed up Sherlock's chest, gripping the collar of his shirt as he bared down on his teeth. He felt as if his jaw would crumble if he bore down any harder, but that didn't stop him from doing so. After a few minutes of throbbing pain, the morphine seemed to kick in, turning the throbs into dull aches. His tail was about half a foot long now with short, blond hairs covering them, and it wiggled on its own experimentally, leaving John to lurch forward as he cried out. The skin still burned and the bones and joints ached, but the growth pain was gone for now. John took the time to lean onto Sherlock's shoulder, merely breathing, silently thanking Sherlock for wiping off his face of the sweat and other bodily liquids that felt unpleasant on his flesh. John didn't know how long it had been anymore; he was too physically and emotionally exhausted to keep track, and he slumped down, his head on Sherlock's lap, his stubbly, little tail wagging. John panted, his tongue hanging out of his mouth as he coughed, and he whined, stuffing his face between Sherlock's thighs.

There, his ears began to fill out: the flappy pieces of skin thickened to where it was more durable and the hair grew thicker. John shook his head, trying to make his ears flap against his skull, trying to keep them from itching, and he groaned before grunting as the growth pains started up again. John growled as he picked his face up from between Sherlock's legs and instead laid himself down on his thigh, biting down into his skin and trousers, as he curled his toes, banging his fist against the couch. It would be okay, it would be way better soon, he told himself. Listening to Sherlock's stories, his now grown ears (though the skin was still new and stretched out, burning hot and itchy) twitched in response, perking to attention with the familiarity of Sherlock's voice. John smiled and nodded as he grunted, unhinging his jaw from Sherlock's leg and instead baring down to where his teeth felt like stubs with the flexibility and durability of a pencil's eraser. John sighed, glancing behind him in order to see his tail, though he didn't see much. Eight inches with patches of golden fur. John, hazy from exhaustion, swatted at it, only to hiss with regret at the way it burned, shooting a rocket of pain through his spine.

"Ah, ah," Sherlock said, softly, reaching out to grip John's wrist and pull his hand away from his tail. "Don't touch it yet. It's too sensitive, in a bad way right now. Looks like it's about halfway over, though. You're doing fantastic, John. Just a few more inches to go." Of course, he needed to grow more fur on it, too, but at least it appeared that his ears were completely finished. The hairs on John's tail were long, just as Sherlock had predicted. They looked silky, and he wanted so badly to touch them, but he knew he couldn't. It was fine; he would wait. Once John's transformation was finished, Sherlock promised himself that he would do whatever John wanted to. It would probably be nothing because John would surely be /exhausted/. Sherlock's transformation twenty years ago-when he was young and spry and full of life and energy-had drained him so much that he'd had to skip class for three days to just /sleep/. John would probably need longer. Sherlock would cater to him. It didn't come easily, or naturally, but he would /make/ himself do it. After putting John through such excruciating pain, it was the least he could do for him, really. John was already beginning to exhibit slight canine tendencies, but that could easily be explained by the fact that the serum was still new in his body; he was still adjusting to it (physically and mentally). The whimpering, the growling-they were both purely canine. The panting would have been one thing, but John's tongue actually slipping out from between his lips turned it into a dog-like action.

John's ears had begun to, slowly, migrate to the top of his head, another sensation that would be none too pleasant for him, but it /would/ make it easier to hide them. They were longer than Sherlock had expected them to be, but not as long as his own, newly-modified ears. Given how slowly John's tail was growing, it was possible that it could take longer than the hour he'd initially guessed. How long had it been already? Sherlock had no idea; normally his internal 'chronometer' would be keeping track, but he'd had other, more important things on his mind. Sherlock had felt like his own transformation lasted /days/. It hadn't, but the excruciating pain had made everything slow down. All he had been able to think about was the throbbing discomfort, the searing agony, the way it felt like his flesh was being ripped open and his bones sawed apart. He regretted ever experimenting on gene splicing to begin with. And, right now, he regretted asking John to 'join him'. At least it was almost over. Hopefully.

John growled in response to Sherlock's touching, though once he realized that it was just Sherlock (and just Sherlock trying to keep him from hurting himself), the growls quickly dispersed into whiny whimpers of pain. God, it hurt. It hurt so badly, like a whole bone was just jamming its way through a hole after it pressed itself out. Which is, morbidly described, what happened initially. John wouldn't be surprised if there was blood, though going by Sherlock's reaction there wasn't any. If there had been whenever Sherlock transformed, he would have told him, and if there hadn't been, Sherlock would be freaking out, even if silently. John would've been able to tell through his eyes, which were slightly weirded out, it seemed, but mostly just concerned. It was heart-warming, except the excruciating pain that had limited John's ability to actually think properly. John clenched down on his jaw, not wanting to bite any part of Sherlock, and he leaned forward, his head stuck between his arm and his torso, the only way he would keep himself from itching. He couldn't reach behind Sherlock to scratch his ears, and to jerk back and pull away would most likely lead to the rubbing of his ears, which were still sensitive. Better not.

John sighed and licked his lips, a bit of drool slithering from his mouth and he used the cushion of the couch to wipe it off as he whined. Another blast of pain, and he straightened his legs, calling out as he curled his toes, his hands forced to turn themselves into fists with nothing to hold onto but themselves. Please, please, let this be over soon. John breathed in and out, trying to focus on that, but it even hurt to breathe, and whenever he focused on /breathing/, he focused on the way his tongue hung from between his lips, which disgusted and embarrassed him as Sherlock was beneath him. And above him, he supposed. John was sprawled out in front of the man, and he realized that this couldn't have been pleasant for him either. Watching John scream, whine, watch his body morph. It was another ten minutes of his tail stretching and prying apart his skin to make room for the new appendage that the itching began. Intertwined with the feeling of agony, the itching was burning and intense, and John jerked back, only to singe his ears. John barked-holy shit, /barked/? John cleared his throat and shook his head violently, his ears flapping against his skull, though that didn't hurt as badly, and he wobbled back away from Sherlock, his fingers clenching the cushion beneath him as he barked madly, wildly, unable to control it.

Sherlock wasn't surprised by the barks. He'd released a fair amount of the noises, too, during his transformation. The way that John was whining, also completely normal, albeit incredibly unpleasant, both for himself to witness and for John to experience. He was panting which was, again, normal. Everything was happening just as it had when Sherlock transformed, although, perhaps, to a lesser degree. Sherlock had been 'bred' with a pure dog, rather than, say, a half of a dog. Essentially, that meant that John was going to be twenty-five percent dog, or less. "I know you're scared," Sherlock told John, rubbing his back gently as he watched the fur on John's tail lengthen into silky strands, although they were matted down, damp with sweat, "but everything's under control. Everything you're going through is normal. The serum's at its peak right now; once the change is over, once you calm down, you'll be back to your old self. It's all right, John, you're okay." The words that spilled out of his mouth felt so…strange. He wasn't a comforter. When he tried, he just felt like he was being silly, embarrassing himself. But still, this was /John/. This was his /partner/. This was the man willing to suffer through excruciating pain just so that Sherlock wouldn't be the sole member of his…species. It was strange to refer to himself as a 'species', mostly because his hybridism had been his own doing in the first place. To this day, Sherlock wasn't sure what he had expected to experience when he took the initial serum, but he'd never fathomed that what had happened, would happen. Sherlock leaned down and pressed a gentle kiss to John's head, nuzzling into the blonde wisps that were there, mixing with gray.

"I love you," he said, hoping that that would provide enough distraction from the remaining inches of John's tail that still had to come through. The appendage, frankly, looked rather awful now. Quivering from pain, still naked in some spots, with long hair in some and short in others, all of it damp with sweat. It appeared to be trying to tuck itself between John's legs, slipping down to nestle in between his arse cheeks. That couldn't be comfortable. It wasn't even comfortable when Sherlock's tail did it, and his didn't have the throbbing, tingling sensitivity that John's did right now. Still, he didn't dare reach out to try and adjust it. Pulling on the hairs or wrapping his fingers around John's tail would probably be enough to make him let out a full howl. "John, I love you. I'll make this up to you, I promise." He kept saying that. Sherlock knew that he was embarrassing himself, demeaning himself (that was how he felt, anyway), but he just wanted John to /know/.

John shouted out as Sherlock rubbed his back, which, along with the rest of his body, was wet with sweat, gleaming across his tan body. His back muscles were tight, clenching at the way John was hunched over, his skull grazing Sherlock's thigh occasionally as he set his head down there. It was taking forever, though John had no idea how long it had actually been. The real torture there was not knowing how exactly to tell how long it had been; Sherlock had said an hour, but for all John knew, it could've been five minutes, stretched by the pain and agony and lack of comprehension from his dreary mindset. What a cruel twist of irony that would be. John's breath shivered as a glob of drool dripped from his hanging tongue, and John growled quietly before whining, his body tensing as his tail stretched out from his body, growing another inch. The burning of itchiness was only on some places, and John could only imagine what his tail looked like: red and blotchy, patches of bare skin like he was some sort of half-skinned cat. Everything's under control. Everything's under control. He kept saying that-the voice... who was it again?

Sherlock. That was it, that was him. John's mind was foggy from pure exhaustion. Control. Control. How could he make the pain go away? He needed control, everything's under control, but he was in /agony/. How could he be in control if everything hurt so badly? Why was everything else so in control? John furrowed his brows and grunted, his tail flickering as it tucked between his arse cheeks, and he could feel it vibrating and trembling between his skin, only burning his arse from the heat and making itself hurt. The angle at which it was curled in order to be in that position was awkward and it pained his not fully grown tail, along with the place it spurted from. John growled and gritted his teeth, looking for something to bite down on. John snapped his teeth, lunging towards the blanket that had been used to wipe off the liquids from his face and gnawing on it. It proved a vague sense of comfort, his body relaxing slightly, though it tightened again with the intense bout of pain shooting in him. John whined, and his legs gave out beneath him tiredly, leaving his head to fall onto Sherlock's lap and he grunted in pain before barking, hesitantly touching his ears. They itched only slightly now, and they were less sensitive, though the base where they sprouted was still aching. John sighed at the words 'I love you', and he couldn't bring himself to say it back, so he just laid down his head, nuzzling against Sherlock's trousers, making small growls of enjoyment. Ignoring the pain and the itches, which were both slowly starting to relieve themselves from his aching, tormented, tortured body, John breathed out, sprawled over the couch. "Sh-Sherlock," he mumbled shakily, his eyes glassy as he looked up to him. "Sherlock... what's it look like?"

"It's almost done," Sherlock assured him, moving his hand up to rub John's hair while the other remained on his upper back. "It's so close to being finished, John. So close. Just hang in there." He didn't comment on the actual appearance of the tail because right now it looked…bad. Just, bad. Mangy and unkempt, as if the tail belonged to a stray dog rather than his lover. Well, he would take care of that for John. They could get in the bath together, hold and kiss and caress one another. John would like that, Sherlock assumed. It would help him get to sleep, too. Sherlock doubted they would do much else tonight. John would be physically and mentally drained, and Sherlock would feel too guilty and uncomfortable about what had happened to be able to relax. Besides, John would probably need time alone to feel his new and modified body parts, and Sherlock would be willing to give it to him. He wanted to be involved, of course, but he didn't want to /hover/. "Almost," Sherlock spoke again. "Almost there, just a little while to go yet. It's long. The fur is, too. Just like I was hoping." Sherlock, as far as aesthetics went, very much preferred long-haired tails like his own as opposed to short-haired ones like that of a Labrador or Doberman. And, he preferred floppy ears. That was why he'd chosen a Newfoundland to get the original DNA from. John's body parts matched it, but with blonde hair instead of black.

The detective was already thinking about what tomorrow would be like. Assuming they went just about straight to bed when this was over, what would tomorrow bring? Teaching John how to tie his tail? Helping John learn how to cover his ears? Would John regret it once he woke up and saw the features in a new light, or would he be glad that he suffered through the pain? /Would/ John's tail and ears be sensitive like his own? Christ, what a horrible twist of fate that would be, if the sensitivity was dulled down as much as the mental changes by the serum being diluted. Would John be afraid to leave the flat? What if someone /did/ see them at some point? What if they went out and Sherlock couldn't control his tail, knowing what John also had hidden down a leg of his trousers? Speaking of…"John," Sherlock began, his voice low, "there /may/ be one other change that I did not mention. My…" He had to pause and swallow, unsure of how to say this even though they had sexual encounters on a regular basis—"testicles grew," he finished quickly. "When I took the serum. They remained human, obviously, you know that, you've seen them, but they…grew. Yours might do the same. Or they might not." He hadn't even /thought/ about that before because they were still /human/. Shit. John would either be pissed or indifferent; it was doubtful that he would be happy to hear such news.

The rest was easy. Well, compared to the last forty-five-plus minutes it was easy. The aching in his tail was dulling, leaving him only with a slight soreness whenever the tail flickered and wagged. The itchiness was becoming less severe as it grew out, the patches of baldness lessening as the hair grew longer and of the same size as the others. His hair looked more brown than it did blond, but that was because of the way the fur was drenched in sweat. His ears were unnoticeable to the man, except for the soreness at the base, but after ten minutes, soreness was all there was. No pain. Definitely no agony. No throbbing. On occasional twitch or discomfort as the tail or ears moved, but other than that, it was nothing. John sighed in relief, actually smiling as he placed his face over Sherlock's crotch.

"Oh, Jesus," he sighed, tired and beginning to laugh. "Oh, my God..." He chuckled dryly and wiped at the sweat on his forehead, his nose beginning to wiggle as he sniffed the air. He was majorly tired and he yawned, exhausted but happy it was over. "Finally," John said at last, completely relaxed as he tried to glance behind him. He was still hesitant to try and touch, but by the look on his face (disgust and vague regret), it was obvious he didn't want to. His tail looked disgusting, twitching madly at the tip with an ugly brown color, and John frowned before groaning. "Damn it," he murmured. "I guess I can't look as cute as you then, hm?" Speaking of, he probably /looked/ awful; an hour of pushing and grunting and sweating, he was bound to look like he'd just run a marathon. Or maybe had gotten run over. John didn't think about tomorrow; he only thought about tonight, thought about /sleep/. God, sleep sounded so good. He would have to be the big spoon, because of his new, sensitive tail, and it would be odd to have Sherlock's tail swinging against his bare crotch. He wasn't wearing pants or trousers for /days/. That's what his exhausted mind decided anyway. He barely even recognized Sherlock was speaking though, his ears fluttering in response to the voice, and he picked his head up whenever he heard the word 'testicles'. John widened his eyes. Holy fuck! "I thought you told me about everything that would happen," John growled, anger scorching his usually blue and kind eyes, making them look fiery with a mad passion. He looked like he would strangle Sherlock; or take a massive bite out of his neck. "You-fucker!"

John rolled off the couch and groaned, clutching at his lower back. "I'm... going to... /kill you/," John snarled, wobbling forwards. The ache in his lower back made it difficult to walk, so his shoulders were hunched as he stumbled into the bathroom. Immediately, his eyes trailed to the ears on top of his head. "Oh, God," he mumbled. They didn't look so good either. John wrinkled his nose and touched the edges of his ear, though it tickled more than anything. John grinned but it faded as his eyes trailed down to his bollocks. "I swear to God," John shouted, "if they grow too big that they throw off my balance, I am going to /throttle/ you." John blinked, wondering how big they were on Sherlock. John groaned and ran his hand through his hair, only to find that his ears were an obstacle. Oh, right. He was going to have to kick that habit. "Sherlock!"

Sherlock breathed a /long/ sigh of relief. Thank /God/ it was over. Watching John go through that had been, in many ways, worse than his own transformation had been, and his had been outright hellish. His tail sprouting while he was stuck wearing trousers and pants, feeling it pressing against the fabric, desperately trying to free itself until he had /finally/ gotten back to his room and been able to push his clothes off. The excruciating pain was something that he would never, ever forget. Nor was the look that had been on John's face, the pained sounds that he had made, the way he resorted to biting and growling and cursing. He had an excuse. Just like he had an excuse to call Sherlock a 'fucker', threaten to kill him. Sherlock actually felt guilty (again) until John told him 'if they grow too big that they throw off my balance'. Ha! So John wasn't actually /that/ mad.

"They won't," Sherlock replied, grateful that he could finally stand up himself. He'd been sitting on his tail for the last hour, two hours, he didn't even know how long it had been, but now it was sore, throbbing in pain. Nowhere near as sore as John's was bound to be, though. "They'll just swell up a little bit," the detective continued, unsure if he was helping the situation or making it worse. "Maybe grow some more hair on them. Hang down a little lower. Don't worry; you aren't suddenly going to have two grapefruits dangling between your legs." The mere thought of that made him chuckle, even though it probably wasn't at all the most appropriate time for that. How else was someone supposed to act after their partner had grown dog ears and a tail? He followed John into the bathroom and sat on the edge of the tub while he took one of John's hands, pulling it to his mouth and kissing it with his lips rather than his tongue. "I know it looks a mess right now," he said, referring to John's tail (although his ears didn't look so good, either), "but once we get it cleaned up, it'll be fine. There's no hurry; we can wait until tomorrow. I'm sure it's still very sensitive, yes?" John's tail was still mostly tucked as far as it could go between his legs—more at the bottom, of course, it actually came up to rest a little against his taint and bollocks—and trembling a little with the urge to /move/, but it was stilled by fear, Sherlock assumed, and discomfort. Sherlock kissed John's hand again, the palm and the back, then his wrist. "How do you feel? Besides the obvious twinges of discomfort in your tail and ears, do you feel all right?" He was mostly referring to the possible morphine overdose, that they seemed to have, thankfully, avoided. The growth in his bollocks, if it happened at all, would be a different story.


End file.
